The Skinny on Fat: How to Get Lay-ed the Right Way

Growing up in the town from which hail the Grateful Dead and Jefferson Starship, fatty foods have always been portrayed as the bogeyman. My parents were amazed that, on the special occasions when they would send me to school with a Twinkie as a treat in my lunch, I was ostracized by the other children as though I were carrying plutonium. When I hit my teens, I rebelled; throughout my college years, I subsisted on bacon cheeseburgers, chili cheese hot dogs, Taco Bell, and Pop Tarts. Now that I'm considerably older, and only mildly more mature, though, I've come to understand the need for balance. While my hippie friends' terror at the sight of a Snickers bar wasn't entirely warranted, neither was my contrarian desire to mainline sausage fat. And so I began to research the actual facts of the matter, the actual pros and cons of fatty foods, and why they were pros or cons.

Any discussion of fats is going to be filled with references to cholesterol. But, what exactly is it? What makes is "good" or "bad"? According to the Harvard School of Public Health:

Cholesterol is a wax-like substance. The liver makes it and links it to carrier proteins called lipoproteins that let it dissolve in blood and be transported to all parts of the body. As we all know by now, too much cholesterol in the blood can lead to problems, such as heart disease.

Cholesterol-carrying lipoproteins play central roles in the development of clogged arteries and cardiovascular disease. The two main types of lipoproteins basically work in opposite directions. Low-density lipoproteins (LDL) carry cholesterol from the liver to the rest of the body. When there is too much LDL cholesterol in the blood, it can be deposited on the walls of the coronary arteries. Because of this, LDL cholesterol is often referred to as the "bad" cholesterol. High-density lipoproteins (HDL) carry cholesterol from the blood back to the liver, which processes the cholesterol for elimination from the body. HDL makes it less likely that excess cholesterol in the blood will be deposited in the coronary arteries, which is why HDL cholesterol is often referred to as the "good" cholesterol.

For more information, check out their website, at http://www.hsph.harvard.edu/nutritionsource/fats.html

1. The Good: Omega-3 Fatty Acids

These fats are not only good for you, they are actually essential for good health, since they cannot be manufactured by our own bodies. They are found in foods like cold-water fish (i.e. sardines, albacore tuna, and salmon), walnuts, flax, and soy. Recent research indicates that omega-3 fatty acids help prevent heart disease and arthritis, among others. They are also highly concentrated in the brain, and are important for cognitive and behavioral function. In fact, infants who do not get enough omega-3 fatty acids from their mothers during pregnancy are at risk for developing vision and nerve problems. Most of us, at this point, have heard about the fact that, despite their fatty diets, citizens of Mediterranean countries tend to have lower rates of heart disease and high blood pressure. While it is true that their diets are fatty, the fats tend not to be meat-based, but rather derive from eggs, nuts, olives, and other vegetable-based sources.

It has been found that those who consume a diet rich in omega-3 fatty acids have higher levels of good (HDL) cholesterol. This diet has also been shown to help hypertension (and lower high blood pressure). In addition, studies of heart attack survivors who have taken omega-3 fatty acid supplements have shown that these people have lower risk of subsequent heart attacks, stroke, and even death. People with diabetes can also benefit from this type of fatty acid, since they tend to have high triglyceride (and low HDL) levels.

Amazingly enough, these fats have actually been shown to help people with depression, and may help with more serious conditions such as manic depression (bipolar disorder), schizophrenia, and ADHD. The omega-3 fatty acids are important components of nerve cell membranes, which means they help nerve cells "talk" with one another. This cell "communication" is essential for maintaining good mental health. In fact, those who ate a diet consisting of fatty fish two to three times a week for five years experienced significant reductions in feelings of depression and hostility. Likewise, a recent study has shown that people diagnosed with bipolar depression who took omega-3 fatty acid supplements (in addition to their medication) experienced fewer mood swings. More studies are being conducted in this area, as well as in the treatment of schizophrenia. Finally, in animal studies, low levels of omega-3 fatty acids have been shows to lower the concentration of certain brain chemicals (such as dopamine and seratonin), which are related to attention and motivation.

2. The Bad: Saturated Fats

Saturated fats are any fats which are solid at room temperature. Period. They are the main dietary cause of high blood cholesterol, which means they put you at high risk for heart disease and stroke. Although it is found in some plants (like coconuts), it is mostly encountered in beef, lard, poultry fat, and dairy products. This is the fat that has been in the news for the longest, and deservedly so.

That said, there are now known to be some health benefits to moderate amounts of saturated fats in the diets. Saturated fats play a positive role in the human body. They provide a good source of stored energy, they cushion the organs against shock, and they insulate vital tissues against the cold...as long as they are not consumed to excess.

3. The Ugly: Trans Fats

This type of fat has been getting most of the attention lately. Rightfully so, too, since it is the most villainous of all the fats. It raises your bad (LDL) cholesterol, and lowers your good (HDL) cholesterol. In other words, not only does it work to clog your arteries, which in turn increases your risk of developing heart disease and stroke, but it also lowers your body's natural defenses against that happening...pretty nefarious stuff.

Most trans fats are what's called "hydrogenated" in nature, meaning that hydrogen has been added to the oils from which they originate, in order to make the fat more solid. These oils, then, make food more shelf-stable, and give them a more desirable taste ("mouth-feel," as my old employer, the low-fat baker, used to call it). As such, they are mostly found in food made in bulk: packaged or pre-made cookies, crackers, doughnuts, and fried foods. Most of the processed foods we've eaten throughout our lives has been rife with trans fats.

The good news is that the push doctors have begun lately to rid our country of this danger is beginning to work. As of January, 2006, the FDA required that all packaged food display trans fat content separately on their Nutrition Facts panel. Shortly thereafter, companies (like Frito-Lay and McDonald's) vowed to stop using trans fats in their foods. As someone who literally starts shaking without a daily dose of salty, fried potatoes, I can vouch that the products that have switched over actually taste better now. I love it when a plan comes together.